This invention relates to load-handling attachments for forklift trucks and more specifically to the means for engaging and disengaging an attachment from the truck and for supporting the attachment when disengaged.
The use of specialized load-handling attachments on lift trucks instead of or in conjunction with conventional lifting forks, such as push-pull attachments or side shifters, is well known in the industry. Such attachments are typically adapted for mounting on conventional ITA (Industrial Truck Association) hook-type lift truck carriages. One attachment so adapted is shown in U.S. Pat. No. 4,165,008.
Two problems in the use of attachments for forklift trucks are the time lost and inconvenience involved in engaging and disengaging such attachments from a truck. Typically, to connect an attachment to a truck, the truck operator must at least drive the truck to a storage area where the attachment is stored upright on a special stand, adjust the level of the load carriage of the truck so that its upper crossbar is below the level of the downwardly opening upper hook of the attachment, drive the truck to position the carriage against the attachment, elevate the carriage until its upper crossbar engages the upper hook, stop the truck, get out of the truck, connect the hydraulic hoses of the attachment to those of the truck, connect an upwardly directed lower hook of the attachment to a lower crossbar of the carriage, get back in the truck, raise the attachment from its stand and drive back to the work area.
A partial solution to the foregoing problems is the use of quick connect-disconnect lower hooks on the attachment which swing into and out of engagement with the lower crossbar of the load carriage. Such lower hooks are disclosed, for example, in a brochure entitled "Cascade QFM Push/Pull (Quick Fork Mount)," published by Cascade Corporation of Portland, Oreg. While the use of such lower hooks does save some time in mounting and dismounting the attachment, it does not eliminate a major source of lost time in such operations, namely, driving to and from the attachment storage area.
The drive to and from the attachment storage area is necessitated because the attachments are not self-supporting in an upright position ready for use. To support the attachments in such a position requires the use of special stands which are kept in such storage areas out of the way of normal lift truck operations and where they can be readily found when needed.
Accordingly, there is still a need to reduce the time and inconvenience involved in mounting and dismounting attachments from forklift trucks.
It is, therefore, a primary objective of the present invention to reduce the time and inconvenience of mounting and dismounting attachments from lift truck load carriages by eliminating the need for storing such attachments on special stands remote from the work area when detached from the lift truck, thereby eliminating time lost in driving to and from the work area in mounting and dismounting such attachments.
A more specific object of the invention is to provide a lift truck attachment which is free standing when detached from a lift truck.
Another major objective is to provide a lift truck attachment which is both free standing and quickly attachable to and detachable from a lift truck.